Method for manufacturing slide fastener chain

Abstract

A waterproof fastener chain includes: a pair of fastener tapes made of polyester resin adjacent to each other at a given space between each side edge thereof, rows of elements respectively attached onto a main surface of the side edge of each of the fastener tapes, and waterproof coated films made of polyester resin respectively formed on a main surface of each of the fastener tapes. An outer surface of each of the waterproof coated films is flat at least at a position where a slider is to pass over, each of the waterproof coated films penetrates into irregularities on the main surface of each of the fastener tapes, a penetration depth of the waterproof coated films into a gap caused by the space of the pair of fastener tapes is not more than thickness of the fastener tapes.

What is claimed is: 
     
       1. A method for manufacturing a waterproof fastener chain, comprising:
 preparing a fastener chain comprising a pair of fastener tapes made of polyester resin adjacent to each other at a given space (s) between each side edge thereof, and rows of elements respectively attached onto a main surface of the side edge of each of the fastener tapes; 
 extruding a polyester resin having a melt viscosity at 200° C. of 50 to 3000 dPa·s from an outlet of a die at 150 to 250° C. to apply the polyester resin onto a main surface of each of the fastener tapes that is opposite to the main surface having each of the attached rows of the elements, and onto the space (s), by curtain coating; and then 
 passing the fastener chain with the applied polyester resin, between a metal roll heated at 100° C. to 250° C., which is arranged on a side of the polyester resin applied surface, and a roll having a hardness of 5 to 50° (JIS K 6253: 2006), which is arranged on a side of the polyester resin non-applied surface, while applying a pressure of 0.1 to 10.0 MPa; and then cooling and curing the polyester resin on the fastener chain. 
 
     
     
       2. The method for manufacturing the waterproof fastener chain according to  claim 1 , wherein a pressure applied onto the main surface of each of the fastener tapes by the polyester resin when the polyester resin is applied by the curtain coating is 1 MPa or less. 
     
     
       3. The method for manufacturing the waterproof fastener chain according to  claim 1 , wherein a distance (g) from the outlet of the die to the main surface of each of the fastener tapes onto which the polyester resin is applied by the curtain coating is from 0.1 to 2.0 mm. 
     
     
       4. The method for manufacturing the waterproof fastener chain according to  claim 1 , wherein the roll arranged on the side of the resin non-applied surface is made of a silicone resin. 
     
     
       5. The method for manufacturing the waterproof fastener chain according to  claim 1 , wherein the method is continuously carried out while conveying the fastener chain in the longitudinal direction.